1. Field of the Invention
The present invention relates to a miniature fault indicator and more particularly to a miniature indicator that senses fault signals and provides a clear visual indication of the condition of the equipment being monitored, the indicator being very small and lightweight and yet extremely rugged for use on high performance aircraft.
2. Description of the Related Art
Detection and notification of problems in potentially dangerous systems are desirable safety objectives. This is especially true of systems in an aircraft. For example, it is believed that excessive voltage in an aircraft's fuel tank poses a dangerous risk of explosion.
Devices, called fault indicators, exist. These usually indicate a fault by causing a light to illuminate or by the rotation of an alternately colored disk or drum. See for example U.S. Pat. No. 3,671,900.
Fault indicators for harsh or demanding environments, such as aircraft, and high performance military aircraft in particular, are difficult to create. Attempts to scale down mechanical devices like circuit breakers have failed because as mechanical devices shrink, friction between movable parts becomes relatively large and difficult to overcome and small and thin parts tend to be too weak to function or are easily fatigued when exposed to high G forces and vibration, commonly experienced in aircraft. Also, large temperature and pressure variations are difficult for very small mechanical devices to handle.